JavaScript implements key-value pairs "map"

Source: Internet
Author: User

javascript  does not have a map, but has a map function-_-!  do it yourself, clothed (function () {try{function directory () {this.key =  new array (); This.value = new array ();} Add Directory.prototype.add = function (key,value) {//key whether to repeat for (var i=0;i<) with the already existing key this.key.length;i++) {if (This.key[i] == key) { throw new error ("duplicate key");  }}//is not repeated, Addthis.key.push (key); This.value.push (value);} Gets Directory.prototype.get = function (key) {for (var i=0;i<this.key.length;i++) {if (this.key[i ] == key) return this.value[i];} Throw new error ("Nothing You Look for  referenceerror");  }//Delete directory.prototype.remove =  function (key) {for (var i=0;i<this.key.length;i++) {if (This.key[i] == key) {// Delete element This.key.splice (i,1) at position I, this.value.splice (i,1); return true;}}  throw new error ("Without you deleting the yarn  referenceerror"); }var myarr = new  Directory (); Myarr.add ("123"); Myarr.add ("Wo", "Bysowhat"), Alert (Myarr.get ("Wo")), Alert (Myarr.get ("123")), Myarr.remove ("123"), Alert (Myarr.get ("123"));} catch (E) {alert (e.message);}}) ();



Complete!

Reproduced....

/* * map objects, implementing map functions  * *  Interfaces:  * size ()       getting the number of map elements  * isempty ()      determine if map is empty  * clear ()       Delete all elements of map  * put (key, value)     add elements to map (Key, value)   *  Remove (key)      Delete the element with the specified key, return true successfully, fail return False * get (key)      Gets the value of the element for the specified key, failed to return Null * element (index)     Gets the element of the specified index (using Element.key,element.value to get the key and value), and fails back to Null * containskey (key)    Determines whether the map contains the specified key element  * containsvalue (value)   Determines if the map contains an element of the specified value  * values ()       get an array of all the value in map (array)  * keys ()       get an array of all the keys in the map (array)  * *  Example:  * var map = new map ();  * * map.put ("Key",   "value")  * var val = map.get ("key")  *&nbsP;...... * */function map ()  {    this.elements = new array ( );      //gets the number of map elements     this.size = function ()  {         return this.elements.length;    }      //determine if the map is empty     this.isempty = function ()  {         return  (this.elements.length < 1);     }     //Delete all elements of map     this.clear =  function ()  {        this.elements = new array ();     }     //adding elements to the map (key, value)       this.put = function (_key, _value)  {         This.elements.push (&NBSP;{&NBSP;&Nbsp;          key : _key,             value : _value         });     }     //deletes the element of the specified key, returns true successfully, fails to return false     this.remove = function (_key)  {         var bln = false;        try {             for  (i = 0; i <  this.elements.length; i++)  {                 if  (This.elements[i].key == _key)  {                     this.elements.splice (i, 1);                      return true;                 }            }         } catch  (e)  {             bln = false;        }         return bln;    }     // Gets the value of the element for the specified key, failed to return Null    this.get = function (_key)  {         try {             for  (i = 0; i < this.elements.length; i++)  {                 if  (This.elements[i].key == _key)  {                     return  this.elements[i].value;                 }            }         } catch  (e)  {             return null;        }     }     //gets the element of the specified index (using Element.key,element.value to get the key and value), and the failure returns null     this.element = function (_index)  {        if   (_index < 0 | |  _index >= this.elements.length)  {            return null;        }         return this.elements[_index];    }      //Determines whether the map contains the element     this.containskey = function of the specified key (_key )  {        var bln = false;         try {             for  (i = 0; i < this.elements.length; i++)  {                 if  (This.elements[i]. Key == _key)  {                     bln = true;                 }            }         } catch  (e)  {             bln = false;        }         return bln;    }     // Determine if the map contains an element of the specified value     this.containsvalue = function (_value)  {         var bln = false;         try {            for  (i =  0; i < this.elements.length; i++)  {                 if  (this.elements[i].value == _ Value) &NBSP;{&NBSP;&NBSP;&NBSP;&NBsp;                bln =  true;                }             }         } catch  (e)  {             bln = false;        }         return bln;    }     // Gets an array of all the value in the map (array)     this.values = function ()  {         var arr = new array ();         for  (i = 0; i < this.elements.length; i++)  {          &nbSp;  arr.push (This.elements[i].value);        }         return arr;    }     // Gets an array of all the keys in the map (array)     this.keys = function ()  {         var arr = new array ();         for  (i = 0; i < this.elements.length; i++)  {             arr.push (This.elements[i].key);         }        return arr;     }}





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Internet Explorer supports the following form:

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Firefox supports the following form:

var errorobj = new Error ();

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Opera, Google Chrome and Safari support the following form:

var errorobj = new Error ([message]);

message
Optional. String that specifies the message of the error. Default is an empty string. Sets the description and messageproperties of the Error object.


JavaScript implements key-value pairs "map"

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